474  
FXUS65 KSLC 041017  
AFDSLC  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SALT LAKE CITY UT  
417 AM MDT FRI JUL 4 2025  
   
SYNOPSIS
 
AFTERNOON CONVECTION IS EXPECTED ACROSS NORTHERN UTAH  
TODAY, WITH POTENTIAL FOR ISOLATED SEVERE WIND AND HAIL. ACROSS  
PORTIONS OF SOUTHERN AND WESTERN UTAH, DRY AND MODESTLY BREEZY  
CONDITIONS YIELD AREAS OF CRITICAL FIRE WEATHER CONDITIONS. HIGH  
PRESSURE RETURNS FROM THE WEEKEND ONWARD.  
 

 
   
DISCUSSION
 
THIS MORNING'S MID-LEVEL WATER VAPOR SATELLITE IMAGERY  
DEPICTS UTAH AND SOUTHWEST WYOMING CURRENTLY WEDGED BETWEEN AN  
UPPER- LEVEL LOW EXITING INTO THE NORTHERN ROCKIES AND A SHORTWAVE  
TROUGH LIFTING INTO THE GREAT BASIN. REMNANT INSTABILITY FROM THE  
EXITING LOW HAS ALLOWED SHOWER ACTIVITY TO CONTINUE OVERNIGHT  
ACROSS PORTIONS OF EASTERN UTAH, BUT IS EXPECTED TO GRADUALLY  
TAPER OFF OVER THE NEXT COUPLE OF HOURS. A MORE ROBUST AREA OF  
SHOWER ACTIVITY IS ALSO ONGOING ACROSS NORTHEAST NEVADA AND  
NORTHWEST UTAH EARLY THIS MORNING, ASSOCIATED WITH INCREASED  
INSTABILITY AHEAD OF A THE AFOREMENTIONED TROUGH. RECENT HIGH-  
RESOLUTION GUIDANCE SUPPORTS THESE SHOWERS CONTINUING TO MOVE  
NORTHEASTWARD ACROSS FAR NORTHERN UTAH THROUGH LATE MORNING. A  
FEW LIGHTNING STRIKES HAVE ALREADY BEEN OBSERVED WITH ISOLATED  
STRONGER CELLS WITHIN THE AREA OF ACTIVITY ACROSS NORTHEAST NEVADA,  
SO CAN'T RULE OUT A COUPLE STRIKES AS THESE SHOWERS MOVE ACROSS  
NORTHWEST UTAH THROUGH THIS MORNING.  
 
AS THIS TROUGH CONTINUES TO LIFT THROUGH THE GREAT BASIN THIS  
AFTERNOON, MODEST FORCING ASSOCIATED WITH THIS SYSTEM WILL COUPLE  
WITH REMNANT MONSOONAL MOISTURE AND EFFICIENT DAYTIME HEATING TO  
PRODUCE WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS NORTHERN  
UTAH. STORMS THAT DEVELOP THIS AFTERNOON WILL HAVE SOME SHEAR TO  
TAP INTO, ESPECIALLY ACROSS NORTHWEST UTAH AND ACROSS THE WASATCH  
FRONT, WHICH MAY LEAD TO SOME MORE ORGANIZED, STRONGER CELLS IN  
THESE AREAS. AS SUCH, THE STORM PREDICTION CENTER HAS PLACED THESE  
AREAS UNDER A MARGINAL RISK (LEVEL 1 OF 5) FOR ISOLATED SEVERE  
WIND GUSTS AND HAIL. GIVEN NUMEROUS EVENTS/FESTIVITIES ASSOCIATED  
WITH THE INDEPENDENCE DAY HOLIDAY, THOSE PLANNING OR ATTENDING  
WILL WANT TO KEEP AN EYE ON THE FORECAST AND HOW THE WEATHER  
ULTIMATELY EVOLVES THROUGH THE DAY. BE PREPARED TO HEAD INDOORS IF  
STORMS APPROACH.  
 
IN ADDITION TO AFTERNOON CONVECTION, THE AFOREMENTIONED TROUGH IS  
EXPECTED TO BRING INCREASED SOUTHWESTERLY FLOW ACROSS THE REGION  
TODAY. EXPECT AN INCREASE IN AFTERNOON WINDS TODAY, ESPECIALLY  
ACROSS THE WEST DESERT AND PORTIONS OF SOUTHWEST UTAH. THESE  
WINDS, IN CONJUNCTION WITH LOW DAYTIME RH VALUES, WILL RESULT IN  
AREAS OF CRITICAL FIRE WEATHER CONDITIONS. SEE FIRE WEATHER  
SECTION BELOW FOR MORE DETAILS. PLEASE CHECK WITH LOCAL OFFICIALS  
REGARDING FIREWORK/FIRE BANS AND RESTRICTIONS TO REDUCE THE  
THREAT OF WILDFIRE IGNITIONS TODAY.  
 
HIGH PRESSURE BUILDS IN QUICKLY BY SATURDAY, THOUGH A CLOSED LOW  
OFF THE COAST OF CALIFORNIA KEEPS TEMPERATURES MODERATED THROUGH  
SUNDAY. THIS LOW IS EXPECTED TO RETROGRADE OFF THE COAST EARLY  
NEXT WEEK, ALLOWING A RIDGE TO GRADUALLY STRENGTHEN ACROSS THE  
WESTERN US THROUGH THE END OF THE WEEK. AS SUCH, TEMPERATURES ARE  
EXPECTED TO CLIMB WELL ABOVE AVERAGE THROUGH THE WEEK, WITH  
WIDESPREAD AREAS OF MODERATE AND LOCALLY MAJOR HEATRISK DEVELOPING  
BY MID-WEEK.  
 

 
   
AVIATION...KSLC
 
EAST-SOUTHEAST TO SOUTHEAST WINDS WILL CONTINUE  
AT THE TERMINAL THROUGH 14Z, THEREAFTER BECOMING SOUTHERLY AND  
MORE GUSTY. ISOLATED THUNDERSTORMS WILL DEVELOP IN THE VICINITY OF  
THE TERMINAL AS EARLY AS 19Z AND MAY PERIODICALLY IMPACT THE  
TERMINAL THROUGH ABOUT 02Z. ANY THUNDERSTORMS WILL BE CAPABLE OF  
WIND GUSTS IN EXCESS OF 50 MPH AND HAIL UP TO 1 INCH. TEMPORARY  
PERIODS OF IFR CONDITIONS NEAR THUNDERSTORMS WILL BE POSSIBLE.  
   
REST OF UTAH AND SOUTHWEST WYOMING
 
AFTERNOON CONVECTION WILL  
DEVELOP AND IMPACT TERMINALS ACROSS NORTHERN UTAH, MAINLY NEAR AND  
NORTH OF A LINE FROM KENV TO KU14. STRONG WINDS IN EXCESS OF 58  
MPH AND HAIL UP TO 1 INCH WILL BE THE MAIN THREATS, ALONG WITH  
LIGHTNING AND BRIEF HEAVY RAIN. THUNDERSTORMS WILL DEVELOP AFTER  
18Z AND CLEAR UTAH BY 02Z. TEMPORARY PERIODS OF IFR CONDITIONS  
NEAR THUNDERSTORMS WILL BE POSSIBLE.  
 

 
   
FIRE WEATHER
 
REMNANT INSTABILITY FROM AN EXITING LOW PRESSURE  
SYSTEM HAS ALLOWED FOR SOME SCATTERED SHOWER ACTIVITY ACROSS  
PORTIONS OF EASTERN UTAH EARLY THIS MORNING, BUT IS EXPECTED TO  
TAPER OFF THROUGH THE REMAINDER OF THE MORNING. ANOTHER WEATHER  
SYSTEM MOVING INTO THE GREAT BASIN TODAY HAS INTRODUCED INCREASED  
INSTABILITY ACROSS PORTIONS OF NORTHWEST UTAH THIS MORNING,  
RESULTING IN SCATTERED SHOWERS AND EVEN SOME ISOLATED  
THUNDERSTORMS ACROSS THIS AREA. ACTIVITY MAY TAPER SLIGHTLY MID-  
MORNING, BUT IS EXPECTED TO INVIGORATE INTO MORE WIDELY SCATTERED  
SHOWERS AND THUNDERSTORMS ACROSS NORTHERN UTAH THIS AFTERNOON.  
ANY STORMS THAT DEVELOP ACROSS THIS AREA TODAY WILL BE CAPABLE OF  
PRODUCING GUSTY OUTFLOW WINDS IN EXCESS OF 50 MPH, IN ADDITION TO  
SMALL HAIL AND FREQUENT LIGHTNING. THIS WEATHER SYSTEM ALSO BRINGS  
INCREASED SOUTHWESTERLY FLOW ACROSS THE REGION TODAY, MAINLY  
ACROSS THE WEST DESERT AND FAR SOUTHERN UTAH. WIND GUSTS OF 30 TO  
35 MPH ARE EXPECTED TO DEVELOP THIS AFTERNOON AS A RESULT, AND IN  
CONJUNCTION WITH VERY LOW DAYTIME RH VALUES, WILL LEAD TO AREAS OF  
CRITICAL FIRE WEATHER CONDITIONS. HIGH PRESSURE BUILDS THROUGH  
THE REMAINDER OF THE WEEKEND, RESULTING IN A GRADUAL WARMING TREND  
INTO EARLY NEXT WEEK WITH INCREASINGLY POOR OVERNIGHT RECOVERIES.  
 

 
   
SLC WATCHES/WARNINGS/ADVISORIES
 
 
UT...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR  
UTZ492-495-497-498.  
 
WY...NONE.  

 
 

 
 
WHITLAM/KRUSE  
 
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE VISIT...  
HTTP://WEATHER.GOV/SALTLAKECITY  
 
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